1. Field of the Invention
The present invention relates to an AC light emitting device, and more particularly, to an AC light emitting device with a bridge rectifying circuit formed therein.
2. Discussion of the Background
As shown in FIG. 1, a conventional AC light emitting device comprises first and second light emitting cell blocks 1200a and 1200b, each of which has a plurality of light emitting cells connected in series on a substrate 1000. The first and second light emitting cell blocks 1200a and 1200b are arrayed in two lines from both electrodes 1600a and 1600b in different directions, i.e., connected in reverse parallel. As shown in FIG. 2, another conventional AC light emitting device comprises a bridge rectifying circuit having a light emitting cell block 1200 and four diodes 1400.
The conventional reverse parallel light emitting device as shown in FIG. 1 does not comprise a rectifying circuit. When an AC voltage is applied to the light emitting device, the first and second light emitting cell blocks 1200a and 1200b are alternately turned on/off. Since only any one of the first and second light emitting cell blocks 1200a and 1200b is turned on in such a conventional reverse parallel light emitting device, there is a problem in that the light emitting efficiency per unit area is low.
In the conventional light emitting device as shown in FIG. 2, the bridge rectifying circuit and the light emitting cell blocks 1200 are connected for enhancing the light emitting efficiency per unit area. However, a reverse voltage is applied to the diodes 1400 of the bridge rectifying circuit in such a conventional light emitting device. When an excess voltage is particularly applied thereto, there is a problem in that the conventional light emitting device is damaged by the excess voltage and thus is not operated.